A Research Of Genesis And Metallogenic Of The Qiongqiate North Pb-Zn Deposit In Southwest Tianshan

The Qiongqiate North Pb-Zn deposit is located in the territory of Aheqi County,Xinjiang,the tectonic position location is located in the south of the combination of the southwestern Tianshan orogenic belt and the Tarim body,it belongs to the thrusting nappe area north of Keping in Keping land margin basin of Tarim block.Based on the study of ore body geology of the Qiongqiate North Pb-Zn deposit,it is found that the lead-zinc deposit is stratified 、 stratoid and lenticular,occureed in karst breccia of the the upper Qiulitage Formation.Ore metal minerals are mainly sphalerite,galena,pyrite and white iron ore,individual natural copper and chalcopyrite,gangue minerals are mainly calcite,quartz,glauconite.Ore structure of its shape-semi-self-shaped structure,gel-like structure,followed by the structure of the account,the ore structure is spherical,lumps disseminated,scattered powder disseminated,dendritic structure.Research on the alteration of the surrounding rock of the deposit shows that the pyrite,calcite and lead-zinc mineralization are closely related.Through the comprehensive study of the deposit geology,geochemical characteristics of ore deposits,and ore-controlling factors,the following understandings have mainly been achieved:(1)Through the study on the relationship between ore-controlling factors and mineralization in deposits,it is believed that the output of lead-zinc deposits is controlled by various factors such as strata,lithology,structure and lithofacies palaeogeography.Faults are ore-bearing fluid migration pathways and control deposit distribution;the output of the ore body is controlled by strata and lithology,the upper part of the upper part of the Qilang Formation and the Qiulitage Formation is composed of argillaceous rock and karst breccia in the lower part,which is an advantageous lithologic combination;the Qiulitage Formation may provide some ore-forming material.(2)Mineralogical studies indicate that the ore’s metal minerals are mainly sphalerite,galena,pyrite,and pyrite.The gangue minerals are mainly calcite,and the wall rock alterations are mainly pyrite and calcine,the deposit belongs a medium-low temperature hydrothermal deposit.(3)The geochemical studies of the deposits show that the hydrothermal calcite C-O isotope indicates that the ore-forming fluid is mainly from the basin fluid,the S isotope of the ore indicates that the sulfur mainly comes from the bacterial reduction of marine sulfate.(4)Through the comparative study of the mineralization geological environment,mineral deposit geology,mineral composition,and lead and sulfur isotopes,the characteristics of the Qiongqiate North Pb-Zn deposit are similar to those of the southwest Tianshan Pb-Zn deposit and the typical MVT lead-zinc deposits in the world.The genetic types of deposits are classified as MVT lead-zinc deposits.(5)The metallogenic model of the Qiongqiate North Pb-Zn deposit is “sedimentaryhydrothermal transformation enrichment”,and the establishment of this metallogenic model will have important guiding significance for the prospecting work in the deep and peripheral areas of the mining area.